1. Field of Invention
The present invention relates to light guides of backlight modules. More particularly, the present invention relates to microstructures of light guides.
2. Description of Related Art
A backlight module illuminates a liquid crystal displays (LCD) from the side or back and can be used in small displays to increase readability in low light conditions and in computer displays and LCD televisions to produce light in a manner similar to a CRT display.
Light-emitting diodes (LEDs) and cold cathode fluorescent lamps (CCFLs) are common backlight module light sources. Presently, the most popular source of backlight module is CCFL, however, with the increasing demand for light and compact displays, the usage of LED backlights has been growing since the LED component is smaller than CCFL in size. However, LED is a point light source with high directivity and thus the liquid crystal display using an LED backlight module would suffer from problems such as hot spots. In order to alleviate this and other problems, diffusive means and/or light guides are designed to direct the light radiated by LED toward the panel of LCD so as to improve the luminance uniformity thereof.
The advancements in LED epitaxy and packaging technology have significantly increased the luminance of LED, and hence manufacturers are eager to cut down the number of the LEDs used so as to reduce the production cost. However, said hot spot issue would get even worse when using fewer LEDs and/or brighter LEDs.
In view of the foregoing, one challenge in the related field is to provide structures and means to obtain good luminance uniformity of LED light source.